Ideal Body Weight Calculator — Devine Formula + BMI Band

How to use

1. Pick imperial (ft + in) or metric (cm) units.
2. Enter your height and select your sex.
3. Optionally add your current weight for BMI and adjusted weight.
4. Press Calculate to see Devine IBW and the healthy BMI band.

General information only — not medical, financial or legal advice. Figures cross-checked against public official sources (IRS / HMRC / NHS / WHO guidance); content last reviewed September 2026. For decisions that matter, confirm with a licensed professional in your country.

About this tool

Ideal body weight sounds like a diet number, but clinically it is a dosing weight: anesthesiologists, pharmacists and ventilator protocols use it for drug dosing and tidal volumes. This calculator applies the Devine formula (1974) — 50 kg for men plus 2.3 kg per inch over five feet, 45.5 kg for women — the same formula behind most hospital reference charts. It also shows the healthy BMI band for your exact height (BMI 18.5–24.9), so you can compare a formula target against a population range. Optionally enter your current weight to see your BMI, your percentage of IBW, and an adjusted body weight used in obesity dosing (IBW + 40% of the excess). All math runs on this page and nothing is uploaded. It is an educational estimate, not medical advice — dosing decisions belong to your prescriber.

FAQ

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